With the Friday bill filing deadline looming, whether Patrick still intends to file a bill is unclear. A Patrick spokesman did not immediately respond to a request for comment.

Despite high-profile praise for the concept — in addition to Patrick and Dewhurst, Gov. Rick Perry is also a supporter — the political will to pass such a program has not materialized. Leaders in the House, including Speaker Joe Straus and Public Education Committee Chairman Rep. Jimmie Don Aycock, have expressed skepticism that such a program could pass in the lower chamber. There is also concern about what critics of the plan view as a lack of accountability it provides for taxpayer dollars.

Last week, state Sen. Eddie Lucio, D-Brownsville, told the Rio Grande Guardian that he intended to file tax credit scholarship legislation that would make a difference for "those in need and those who are falling through the cracks."

He said his proposal was not a voucher system, but was about "helping a category of students who have fallen on hard times, who are disadvantaged economically and who need our help to make it through the system."

"We're not planning on a bill of that nature," he said. "We don't have a draft out, and there's no language to file."

When contacted by the Tribune, Collins said he could not comment beyond what was reported in the Houston Press.

Paxton's legislation would allow "educationally disadvantaged" students at public schools rated "unacceptable" under the state's accountability system to use the scholarships to attend any accredited nonpublic school, including religious institutions. Businesses contributing to "certified nonprofit education assistance organizations" would receive state franchise or insurance premium credits in exchange. The program would intercept the money before it hit public coffers, which would allow private schools to remain outside of regulations and accountability measures applied to the state's public schools.

A former state representative serving his first term in the Senate, Paxton sits on the upper chamber's education committee. A staunch social conservative who ran against Straus for House speaker three years ago, he is a longtime supporter of voucher programs. He filed a similar tax credit bill in 2003.

Paxton's office has not yet responded to a request for comment.

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